Allow deleting own suggestions in Suggest phase and surface delete chip

Program.cs

@@ -205,6 +205,22 @@ api.MapPost("/suggestions", async ([FromBody] SuggestionRequest request, HttpCon
     return Results.Created($"/api/suggestions/{suggestion.Id}", new { suggestion.Id });
 });
 
+api.MapDelete("/suggestions/{id:int}", async (int id, HttpContext ctx, AppDbContext db) =>
+{
+    var phase = await GetPhase(db);
+    if (phase != Phase.Suggest)
+        return PhaseMismatch(Phase.Suggest, phase);
+
+    var player = await GetOrCreatePlayer(ctx, db);
+    var suggestion = await db.Suggestions.FirstOrDefaultAsync(s => s.Id == id && s.PlayerId == player.Id);
+    if (suggestion == null)
+        return Results.NotFound(new { error = "Suggestion not found." });
+
+    db.Suggestions.Remove(suggestion);
+    await db.SaveChangesAsync();
+    return Results.NoContent();
+});
+
 api.MapGet("/suggestions/all", async (AppDbContext db) =>
 {
     var phase = await GetPhase(db);